The invention relates to a controller module for use in a work station, in particular, an industrial work station which is an element of a manufacturing control system. Manufacturing, in its broadest sense, encompasses various primitive, and undivided, operations on a product, such as test, storage or transformation. A work station thus comprises a controller module and one or more execution modules. An execution module may influence or observe the product in its environment; the product may thus be changed in this environment. A work station controller module as recited supra has been described by Scott and Strauss, "Work station control in a computer integrated manufacturing system", National Bureau of Standards, Washington, D.C., May 1984. Like the reference, the controller module of the present invention is adapted for use in transforming discrete products of all type. Transformation may be realized in manufacturing operations of all kinds, such as changing the product shape, assembling, modifying physical properties, sorting, testing, moving, packaging, combining and many others.